This invention relates to the field of test probing, and more specifically to buckling beam test probing.
As circuits, such as integrated circuits on semiconductor chips, become increasingly complex, it is becoming more important to test the circuits for any errors. However, as the circuits become more and more dense (have more contact points), it is also becoming increasingly harder to perform the tests.
One method of testing circuits is called buckling beam probing. Buckling beams are conductive wires which are connected to a testing apparatus and which are used as contact probes. In one buckling beam probing assembly, a large number of buckling beams are arranged in a frame which includes guide plates which are drilled according to the footprint of contact points of the circuit being tested. The ends of the buckling beams are brought into contact with the contact points of the device being tested and put under an axial stress which causes the beams to deflect or buckle laterally. The lateral buckling helps the probe assembly adapt to irregularities in the surface of the device being tested and to adapt to different heights of the contact pads or points. Some buckling beams include a pointed tip to help penetrate any oxide buildup on the contact being probed.
Present buckling beam assemblies can be improved. One problem is that due to the variations in probing over-travel and/or contact point height, a probing process can induce a shearing force in the contact point, especially when pointed tip buckling beams are used. This can cause either reliability problems or permanent damage of the intended contact.